Does any reputable merchant sell it already blessed over the internet...the water and the beeswax.?
water.pdf
You should be careful about buying previously blessed sacramentals, there being two reasons for this;
A) if you pay full value for the object, but without any extra charge for the blessing, it loses it's blessing.
B) if you pay extra for the blessing, you are in fact committing Simony.
As B is a mortal sin -thus not an option-, A would be your only recourse. As you would have to get it blessed any ways, you really are back to square one. So no, you can't buy blessed objects.